The big BMW 1 Series news is the upcoming M-badged coupe, but we mustn't forget that an all-new 1er is currently in development. Our spies have just recently snapped this five-door model testing, concealing what could be a highly anticipated turbocharged four-cylinder engine.

Sources suggest this new four-pot could be a new tri-turbo setup, meaning the 1 Series would still be plenty powerful and could replace the naturally aspirated 3.0-liter inline-six currently used in 128i models. Additionally, we won't rule out the possibility that BMW is testing the new N55 twin-scroll single-turbo for use in the 1 Series, since that mill seems to quickly be replacing the current twin-turbo 3.0-liter setup.

Expect the next-generation 1 Series to hit the road sometime in 2012. With that in mind, a debut at next year's Geneva Motor Show doesn't seem out of the question.